After extensive inquiry and many personal experiments, the author has found a cooking-stove constructed on true scientific principles, which unites convenience, comfort, and economy, in a remarkable manner; and this is the one referred to in the kitchen of the cottage described in Chapter IV. Of this stove drawings and descriptions will now be given, as the best mode of illustrating the practical applications of these principles to the art of cooking, and to show how much American women have suffered, and how much they have been imposed upon for want of proper knowledge in this branch of their profession. And every woman can understand what follows with much less effort than young girls at high-schools give to the first problems of Geometry—for which they will never have any practical use, while attention to this problem of home affairs will cultivate the intellect quite as much as the abstract reasonings of Algebra and Geometry. [Illustration: Fig. 36.] Fig. 36 represents a portion of the interior of this cooking-stove. First, notice the fire-box, which has corrugated (literally, wrinkled) sides, by which space is economized, so that as much heating surface is secured as if they were one-third larger; for the heat radiates from every part of the undulating surface, which is one-third greater in superficial extent than if it were plane. The shape of the fire-box also secures more heat by having oblique sides—which radiate more effectively into the oven beneath than if they were perpendicular, as illustrated by Figs. 37 and 38. It is also sunk into the oven, so as to radiate from three instead of from two sides. In most other stoves, the front of the fire-boxes with their grates are built so as to be the front of the stove itself, and radiate outward chiefly. [Illustration: Fig. 37. Model Stove.] [Illustration: Fig. 38. Ordinary Stove.] The oven is the space under and around the back and front sides of the fire-box. The oven-bottom is not introduced in the diagram, but it is a horizontal plate between the fire-box and what is represented as the “flue-plate,” which separates the oven from the bottom of the stove. The top of the oven is the horizontal corrugated plate passing from the rear edge of the fire-box to the back flues. These flues are three in number—the back centre-flue, which is closed to the heat and smoke coming over the oven from the fire-box by a damper, and the two back corner-flues. Down these two corner-flues passes the current of hot air and smoke, having first drawn across the corrugated oven-top. The arrows show its descent through these flues, from which it obliquely strikes and passes over the flue-plate, then under it, and then out through the centre back-flue, which is open at the bottom, up into the smoke-pipe.